The present invention relates to electric fan heaters. More particularly, although not exclusively, the invention relates to an electric fan heater having its fan blade located behind its heating elements and comprising smooth profiled louvres which provide a broadening air flow path to reduce operational sound levels.
Known electric fan heaters comprise one or more electric heating elements situated behind the fan. That is, the air is preheated prior to its interaction with the fan. The fan then draws preheated/low-density air through the heating elements and blows the heated air through simple safety louvres at the front. There are several problems associated with such fan heaters. Firstly, the fan blade and electric fan motor are subject to air-contact with air that is already heated by the heating element(s) and must therefore be designed to withstand such temperatures. Secondly, as the fan is acting on low-density/expanded hot air, it must operate at a speed higher than that at which it would have to operate at room temperature to drive the same volumetric flow rate of air. It creates unnecessary fan/motor noise. Thirdly, the close proximity of the fan to the safety louvres at the front of the heater body causes turbulent airflow through the louvres—which turbulence interacts with the louvres to create high operational noise levels.